Produce, such as fruit, is typically cooled after harvesting to maintain the quality of the harvested products throughout the supply chain. By maintaining a low produce temperature, deterioration in produce quality is reduced. This is particularly the case in situations where the produce needs to be transported for a long period.
The initial hours after harvesting are extremely important with respect to reducing product temperature. This is especially the case where products have a high respiration rate, as this significantly reduces deterioration of the products. Respiration is the process by which plants, for example, take in oxygen and give out carbon dioxide. Many producers have a stringent postharvest regime to maintain the produce at the highest possible standard. One such technique is post harvest pre-cooling. Pre-cooling is generally carried out in cool rooms using forced-air or static air cooling techniques.
Forced air pre-cooling reduces produce temperature by passing air over or through packaging of freestanding containers or palletised containers. In a typical forced air pre-cooling process, the following steps are performed:                a. two rows of pallets are positioned with a divide between them;        b. a heavy duty tarpaulin is pulled across the top and down front of the divide;        c. a fan at the opposite end of the divide draws air from the cool room, through the palletised containers, down the divide and discharges back into the cool room.        
Static cooling is carried out by placing palletised products in cartons directly in cool rooms and relying on natural air currents in the cool room, as well as conduction through the cartons, to reduce the produce temperature. Static air cooling is significantly slower than forced air cooling.
Much research has been carried out trying to understand the factors affecting cooling operations and cooling times. Research has previously been undertaken in the following areas with a view to improving cooling operations and cooling times:                a. the heat transfer characteristics of produce, such as fruit and vegetables;        b. air flow rates and volumes; and        c. vent patterns.        
Container design has a significant effect on the cooling rate of products for both types of cooling methods. However, optimisation of box vent design and stacking strength may not have previously been systematically investigated. Rather, it was generally understood in the art that produce boxes should be constructed having:                a. 6% to 8% open vent area; and        b. well distributed vents located away from the corners.        
An example of a box 1 with such a design is shown in FIGS. 1a to 3c. It was commonly thought that vents located near the corners of the box significantly reduce the stacking strength.
There are many box designs available on the market for transportation of fresh produce, some with vents and others without, depending on the application requirements. Vented boxes are generally over engineered to compensate for strength loss as a result of including a plurality of vents. The vents have traditionally been placed by designers in similar positions regardless of box manufacturer, as this was thought to be an optimal configuration.
Traditional positioning of vents on a vented produce box includes:                a. on box scores (half on top face, half on side and similar for bottom/side);        b. a short distance from the corner; and        c. equally spaced across the centre of sides.        
These designs have been available for several decades with little to no change.
Boxes have previously been designed by focusing on understanding fundamental principles of heat transfer and cooling of produce. Several research groups have purpose built equipment for experimenting with variables and understanding heat transfer. However, this equipment has not been used to design more efficient boxes. A major hurdle to further progress in box design is lack of cooling information when designs are changed. Hence, designs tend to be conservative and obvious with intuition being used as the measure of cooling performance.
It is generally desirable to find a design for a box which has an optimal ventilation system whist reducing the impact on stacking strength.
It is generally desirable to overcome or ameliorate one or more of the above mentioned difficulties, or at least provide a useful alternative.